Everything happens somewhere. Making informed decisions means knowing something about the geography of the environments in which we live and work. In every case we collect and combine information from multiple sources.

At one extreme, for example, predicting the impacts of global warming requires you to understand the state of and interactions between the atmosphere and biosphere whereas at a local level the benefits of knowing where someone is making an emergency phonecall from are only realised if you can match that location to the nearest police, fire or ambulance station. It follows that it is essential you know something of how position is recorded in different ways and are then able to join-up data from different sources.

To quote Andrew Pinder, HM Government e-Envoy, "Geography is one of the key common frameworks that will enable us to link information together and boost efficiency in government."

It is conventional to think of geographic information consisting of three elements. We record data for attributes, position and time, and we use metadata to describe a dataset.


* Planning the delivery of health services
* Managing the coastal zone and flood defences
* Managing epidemics
* Retail store location
* Monitoring pollution
* Assessing environmental hazards
* Access to the countryside and public rights of way
* Monitoring land-use and recycling contaminated land
* Coordinating the actions of the emergency services
* Crime and disorder analysis
* Vehicle navigation and traffic management
* Using GPS to track transport fleets and parcel deliveries
* Planning the built environment
* Delivering water, gas and electricity to customers
* Planning and managing sporting and cultural events
* Planning safe school routes
* Public transport planning and provision
* Buying and selling of commercial and residential property

This topic is concerned with the positional aspects of the data and some of the ways in which we use metadata to record and communicate that information.

Position is recorded in terms of a geometry and a spatial reference. The geometries are stored in either a raster or vector data model. In sourcing spatial data you require skills to capture data position and/or interpret the documentation that accompanies secondary data sources. To integrate spatial data you need to handle different coordinate systems and convert between raster and vector data models.